Apparatus for coiling material



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Nov- 14, 1933- L IVERSEN'Y ET AL APPARATUS FOR COILING MATERIAL Filed Aug. 13, 1930 11 Sheets- Sheet ll Patented Nov. 14, 1933 APPARATUS FOR ooI ING MATERIAL Lorenz Iversen, Pittsburgh, Robert E. Noble, Grafton, and Gustaf L.' Fisk, Pittsburgh, Pa., assignors to Mesta Machine Company, Pittsburgh, Pa., a corporation of Pennsylvania Application August 13, 1930. Serial No. 474,992 21 Claims. (Cl. 242-78) The present invention relates broadly to the art of metal working, and more particularly to an apparatus generally referred to as a coiler efiective for coiling relatively long pieces of material,

such as metal strip, and to a method of more effectively carrying out such a coiling operation.

The word strip is herein used generically as a word of definition and not as a word of limitation, and includes any material of a substantially rectangular cross-section adapted to bewound into a helix with the coils in generally superimposed relationship one to the other.

Strip is usually made in a rolling mill, either hot or cold, and in relatively long lengths. To facilitate handling, it is frequently formed into coils as it'issues from the mill. These coils are generally of two distinctive types, i. e., either the tight coil or the loose coil. The tight coil is one formed by having the inner surface'of each succeeding layer in contact with the outer surface of the preceding layer. The loose coil is one that is formed with an appreciable space between the succeeding layers. For certain purposes a loose coil is of particular advantage as, for example, when the strip is to be pickled. Pickling is a process well-known in the art and consists in immersing metal in a cleaning solution, such as an acid bath, to remove rust and scale from the metal surface. With a loose coil, the pickling solution easily penetrates between the layers and is thereby enabled to effectively clean all of the surface.

. In the practical art, one or more coilers are usually arranged at or adjacent thev delivery end of a strip rolling mill. Preferably, they should receive the'end of the strip as it issues from the mill, and form it into either a tight or a'loose coil. Provision must be made for receiving the strip and properly starting it so as to form the coil smoothly and accurately; for rotating the coil at the proper speed to form' a tight or loose coil as desired; to compensate for the constantly increasing diameter of the coil as successive layers are added to it; and for discharging the finished coil from the apparatus. The present invention has for certain of its objects the provision of a method and apparatus by means of which desirable results in these and other respects, may be satisfactorily and continuously obtained.

In the accompanying drawings, we have shown for purposes of illustration, a preferred embodiment of the invention. In the drawings:

Figure 1 is a side elevational view of a coiler constructed in accordance with the present invention;

- Figure 2 is a view partially in elevation and partially in vertical section of the coiler illustrated in Figure 1; 1

Figure 3 is a sectional view on the line III--III of Figure 2;

Figure 4 is a diagrammatic sectional view taken in the same plane as Figure 2 and illustrating the beginning of a coil forming operation;

Figure 5' is a view similar to Figure 4, illustrating a completed coil ready for removal from the coiler;

Figure 6 is a detail sectional view, on an enlarged scale, on the line VI-VI of Figure 1, and illustrating a portion of the balancing mechanism;

Figure 7 is a partial side elevational view of the balancing mechanism of Figure 6;

Figure 8 is a view partly in longitudinal section and partly in side elevation, and illustrating more particularly the coil discharging mechanism;

Figure 9 is anend elevational view of the discharging mechanism; I

Figure 10 is a detail sectional view, on. an enlarged scale and partly in elevation, illustrating a coiling roller and its supporting and driving means, the view being taken along the line X-X of Figure 11;

Figure 11 is a vertical sectional view along the line XIXI of Figure 10 looking in the direction of the arrows;

Figure 12 is a view partly in section and partly in elevation, along the line XII-XII of Figure 11, and looking in the direction of thearrows;

Figure 13 is a longitudinal sectional view through the coil forming mandrel;

Figure' 14 is a detailed sectional view along the line XIV-XIV of Figure 13;

Figure 15 is a top plan view of the swinging guide for delivering material to the coiler;

' Figure 16 is a sectional view along the line XVI-XVI of Figure 15;

Figure 17 is a detailed sectional view illustrating the pinch or feed rollers, their mounting, and. driving means; and.

Figure 18 is an end elevational view, partly broken away, of the mechanism illustrated in Figure 17.

In carrying out the present invention there may be provided a coiling apparatus comprising a base 2 having secured thereto and projecting upwardly therefrom, spaced housings 3 and 4. These housings may carryat their upper porthe housings.

tions, as illustrated in section in Figure 3, a housing cap 5. This cap, as shown in Figure 1, is formed in one of its sides with a' feeding opening 6 by means of which the material to be coiled may be passed to the mechanism between The feeding opening 6 is conveniently of the general cross-sectional shape illustrated, for example in Figure 2, to provide a gradually contracting opening terminating in a throat '7 adapted to deliver the material to a pair of pinch or feeding rollers 8 and 9 extending longitudinally of the base 2 and of such constructidn as to be rotatably carried at their 0pposite ends in suitable bearings 10 in the respective housings 3 and 4. The mounting of the pinch rollers, together with the adjusting and driving means therefor, are illustrated in detail in Figure 17 of the drawings. From this figure it will be apparent that the lower pinch roller 9, while rotatably mounted in the housing, is not mounted for vertical adjustment therein. The desired adjustment between the pinch rollers is preferably obtained by adjusting the upper roller 8. This adjustment may be obtained by providng the bearings 10' with threaded extensions 11 projecting upwardly through suitable supports 12 secured to the housings, and co-operating with adjusting and lock nuts 14. Provided within the supports 12 and surrounding the extension 11, are coiled springs 15 effective for pressing the roller 8 toward the roller 9 for gripping the materialfed therebetween.

We preferably. make provision for driving the pinch rollers independently of the portion of the apparatus to, be hereinafter described, desirable results in this respect being obtained by the use of a separate variable speed motor 16 carried by motor bracket 17 secured to the housing. The armature shaft 18 of the motor carries a driving pinion 19 engagingwith one of the intermeshing gears 20 carried by suitable extensions 21 on the pinch rollers. By reason of this construction, the pinch rollers may be independently driven at any desired speed.

After having passed between the pinch rollers, the material enters the throat 22 of a swinging guide 23, the construction of which is illustrated in detail in Figures 15 and 16 of the drawings. .At its end adjacent the pinch rollers the swinging guide is pivoted about a shaft 24 extending in substantially parallel relationship to the pinch rollers, and carried by the housings 3 and 4. This mounting of the swinging guide maintains the desired operative relationship between the throat therein and the pinch roller pass regardless of the position to which the guide is swung as hereinafter described At its opposite end, the guide is provided adjacent each side thereof with spaced lugs 25 adapted to receive pins 26 forming pivotal mountings for the lower ends of guide operating links 27.

Adjacent the links 27, the guide also carries a material deflecting and shaping roller 28 adapted to be driven by a variable speed motor 29, also mounted on the swinging guide so as to move therewith, and effective for driving the roller 28 through the gearing 30.

Also carried by the base 2 and projecting up wardly therefrom outside of the space occupied by the housings 3 and 4, is a mandrel support 31 (see Figures 1 and 3) forming a mounting for a stationary mandrel 32. The lefthand end of the mandrel as viewed in the figures referred to, overhangs the mandrel support, and projects through the housings so as to extend substantially continuously therebetween. Journaled in the-projecting end of the mandrel is a roller 33 adapted to cooperate with the roller 28 carried by the swinging guide. To this end, the mandrel roll 33 is preferably so mounted that its surface will project slightly above the surface of the mandrel. The mandrel roller is in turn adapted to be driven by a variable speed motor 34 through suitable gearing 35.

Substantially completely surrounding the mandrel 32 is a series of pairs of coiling rollers 36- 36, 3737', 38--38 and 39'3 9. Each pair of coiling rollers is carried by a movable support 40 in the general manner illustrated in Figure 2, and as illustrated in detail in Figures 10, 11 and 12, the supports 40 extending between the housings 3 and 4 and substantially parallel to'the mandrel 32. As illustrated more particularly in Figures 10 to 12 the supports 40 provide spaced arms 41 at their opposite ends which arms, with the supports in position, extend in a direction generally radially of the mandrel as will be apparent from Figure 2 of the drawings. These arms at their inner portions carry pins 42 forming pivotal mountings for curved arms 43 of a series of bell-crank levers 44, 45, 46 and 47. The construction is such that as the bell-crank levers are turned in a clockwise or counterclockwise direction as viewed in Figure 2, the supports 40 with the coiling rollerscarried thereby may be moved outwardly from, or inwardly toward, the mandrel.

' To insure a movement in a generally radial direc tion, the arms 41 at their outer ends carry pins 48 forming pivotal mountings for one end of each of the links 49, the opposite ends of these links being piyotally carried by suitable stud pins 50 projecting inwardly from the respective housings as illustrated for example in Figure l. The links 49 together with the curved arms 43 of the respective bell-crank levers give a controlled movement to the supports'as will be readily understood.

- In accordance with the preferred embodiment of our invention, each pair of coiling rollers is adapted to be driven independently of the rollers constituting another pair. This operation we accomplish by securing to each of the supports 40 a variable speed motor 51, which motors have armature shafts 52 carrying pinions 53 meshing with gears 54 on extensions 55 of the coiling rollers, whereby the rollers may be driven in the direction illustrated by the arrows in Figure 11.

In addition to the curved arms 43 before described, the bell-cranks 44, 45,46, which are suitably carried between the housings 3 and 4, are provided with outwardly projecting arms 56 extending in generally diverging relationship, while the bel1-crank47 is provided with a single arm 57. These arms are all interconnected by means of links 58 having pivotal connections 59 with the respective arms. One of the arms 56 of the bell-crank 44 is also connected by a. link 60 to an arm 61 projecting outwardly from the hub of a bell-crank 62. The arms 63 of this bell-crank have pivotal connections 64 to the guide swing links 27 before described. By reason provision must be made for effecting such a movement in predetermined speed relationship to the building up of the coil itself.

For accomplishing such movement, we provide the bell-crank 46 with a third arm having a pivotal connection 66 to one end of a pitman 67. This pitman at its opposite end is provided with a slot 68 within which a crank pin 69 of a crank arm 70 is operated. As will be p arent more particularly from Figure 1 of the drawings, the crank arm 70 may be rotated by a shaft 71 extending through the'housing 4 and journaled in a suitable bearing 72 carried by the base 2. For rotating the crank shaft 71 there is provided a variable speed motor 73 carried by base 2,- the motor being operatively connected to the crank shaft through suitable reduction gear (not shown), located within the gear casing 74, and effective for driving the shaft 71 at any desired speed, further speed variations being obtainable by reason of the fact that in this case, as in the case of the other motors, the motors themselves are ofvariable speed type. The motor "73 is effective for driving. the crank arm 70 in a counterclockwise direction as viewed in Figure 2. As

the crank arm moves from its position illustrated 7 ished at the will of the operator.

in Figure 2, in a counter-clockwise direction, it

will be apparent that its effect on the bell-cranks operated thereby is, as to the movement produced, a gradually decreasing one. The lengths and positions of the various cranks in the system, and the mechanism just described, may be so proportioned as to approximate the decreasing rate at which the diameter of the coil increases.

If the speed of the crank arm 70 is not properly adjusted so as to provide amovement of the character just described, and is so slow that the coiling rollers are not moved outwardly from the mandrel 32 as rapidly as the diameter of the coil increases, the slotted opening 68 in the pitman 67 will permit these rollers to be forced outwardly by the coil itself without damage to the coiler.

Since the slot 68 provides what may be termed a lost-motionconnection effective in one direction, and permitting a relatively free outward movement of certain parts of the mechanism, it will be apparent that if suitable balancing means for such mechanism were not provided, such mechanism would tend at all times to drop freely away from the mandrel and thereby prevent a proper coil formation. In order to preclude the possibility of such an operation, balancing mechanism of the general character illustrated more particularly in Figures 6 and 7 is provided.

This mechanism comprises a spring balance cylinder 75 within which is mounted a balance spring 76 bearing at one. end against the cylini der, and at its opposite end against a suitable follower 77. The position of this follower with respect to a yoke or cross-head 78 is adjusted by means of a screw 79, this screw enabling the tension on the spring to be increased or dimin- Extending through the cross-head 78 is a pin 80 to the outer ends of which are pivotally connected links 81; pivotally connected at their inner ends to a yoke 82. The yoke 82 is adjustably carried by an arm 83 secured to the bell-crank 46, adjustment being obtained by means of a screw 84 threaded at one end into the yoke 82, and at its opposite end carrying-a worm-wheel 85, co-operating with a worm 86 adapted to be rotated by a hand-wheel 87 (Figure 1). This construction enables the yoke 82 to be adjusted inwardly or outwardly along the arm 83 and thereby adjusts the leverage through which the balance spring is effective for exerting its balancing action. The size of the spring 76 is such as to properly balance 80 not only the weight of the parts, free outward movement of which it is desired to prevent, but also the weight of the coil itself. The adjusting means 79 for changing the tension of the spring itself, as well as the adjusting means for the yoke 82, enable a suitable adjustment to take care of the weights of diiferent'coils. The cylinder 75 is provided with slots 88 in'its side walls permitting movement of the pin 80 as the diameter of the coilincreases, this movement being such as to place a gradually increasing tension on the spring 76, such as to approximately compensate for the increase in the weight of the coil as it increases in diameter.

A coil having been formed arou'nd the man'- drel, provision must be made for its-discharge from the apparatus. Such a discharge is preferably eifected by moving the same axially of the mandrel, the housing 3 being formed with an opening 'of suificient size to permit such a 00 discharging movement of the finished coil. Prior to the discharging operation, the parts of the apparatus which have been hereinbefore described, will be moved to substantiallyt'he position illustrated in Figure 5, this figure showing the mandrel 32 as having a finished coil C in position therearound, this coil being herein shown as of the tightly wound type. The parts having been moved to this position, discharge of the coil is effected by mechanism illustrated more 11 0- particularly in Figures 8 and 9 of the drawings.

For moving the same axially of the mandrel,

there is provided a pair of air cylinders 91 preferably disposed on opposite sides of the mandrel and overlying the mandrel support 31. The

pistons (not shown) within the cylinders 91 have rods 92 which areconnected to the ejecting ring 0 90, the ring during itssliding movements being guided along the mandrel by the provision of projections 93 formed thereon and movable-within guideways 94 in the mandrel body. These guideways also insure the movement of the projections on the ejecting ring under the inside layer of the coil, as will be apparent.

The construction of the coiler having been described, the operation thereof will now be set forth in detail. Preparatory to an actual coil-. ing operation, the parts of the apparatus are moved into the general position illustrated somewhat diagrammatically in Figure 4 of the drawings, the bell-cranks 44, 45, 46, 47 and 62 being permitted to swing to the extent required to bring the parts into this position by mounting each of the bell-cranks on studs 95 at'the opposite end portions thereof, the studs being carried by the respective housings 3 and 4. This position of the parts having been obtained-the motor 16 is started for driving the pinch rollers 8 and 9; the motors 51 for driving the coiling rollers 3636., 37-37, 38-38 and 39-39 are energized; and the motors 29 and 34 respective-, ly are likewise energized so that all of the rotative parts of the apparatus are caused to rotate in the desired direction at the requisite speed for the coiling operation. The strip to be coiled enters the coiler between the pinch rollers 8 and 9, the peripheral speed of which is properly of these three rollers is so adjusted with respect to each other as to bend the strip into a circle having a diameter slightly greater than the diameter of the mandrel 32. The strip, bent in the manner described, is then carried around the mandrel by the coiling rollers. After the first layer. of the coil has been completed, this condition being illustrated in Figure 4, the form of the coil is determined, and the driving of the mandrel bending roller 33 may thereupon be discontinued. Such an operation is preferably effected by an automatic circuit controlling means (not shown) for the motor 34: although it may be controlled manually by the operator. At this time, also, it is desirable to energize the crank operating motor 73 whereby as the successive layers increase the diameter of the coil, the swinging guide and its associated parts, together with the pairs of coiling rollers, are moved outwardly from the mandrel in the manner hereinbefore described.

The peripheral speed of the various rollers as well as the speed at which they are moved away Tfrom the mandrel, is regulable by changing the speed of their respective driving motors whereby it is possible to produce either a tight or a loose coil. If the peripheral speed of the coiling rollers is made slightly greater than the speed at which the strip enters the coiler so as to keep a slight tension on the strip, and the rollers are drawn away from the mandrel at the same speed as the coil increases in diameter, a tightly wound coil is produced. On the other hand, if the peripheral speed of the coiling rollers is adjusted to the speed at which the strip enters the coilers and they are drawn away from'the mandrel. at a faster rate than the rate determined by the thickness of the succeeding layers of the coil, a coil of any reasonable degree of looseness may be formed.

The coil having been completed in the manner described, the crank driving motor 73 is continued in operation for a sufiicient period of time to insure the movement of the parts into the position illustrated in Figure 5. The completed coil is thereupon ejected from the apparatus by admitting fluid pressure through the ejecting cylinders 91.

Rather than impose upon the operator the responsibllity for stopping the crank operating motor 73 with the parts thereof .in the desired position, the apparatus preierably includes a limit switch 96 driven from the shaft 71 through suitable sprocket and chain connections 97; whereby the motor is automatically stopped at, predetermined positions ofthe crank pin 69.

The method here'n described of controlling the relative tightness or looseness of the coil, thereby enabling a coil wound within comparativcly wide limits to be effectively produced, as well as the mechanism by means of which such changes may be effected, constitute certain ad- Vvantages of the present invention.

' -neous movement of the various parts in certain predetermined relationship to the increase in the ,that changes in the construction and operation of the parts, as well as in' the method of, DIOdIlcing' the coil, may be made without departing either from the spirit of our invention or the scope of our broader claims. Weclaim: 1 1. In a coiler, an inside bending roller, afplui rality of outside coiling rollers therea'round, means for effecting movement of said coiling rollers outwardly from the bending roller, and means mov-.

able with the coiling rollers for rotating the same during the outward movement.

2. In a coiler, a mandrel, a plurality of coiling rollers circumferentially disposed relative to said mandrel, and a movable guide carrying a roller. so disposed as to lie. substantially in the circular path of said coiling rollers, 'ther' being another roller within said mandrel. and directly co-operating with said guide. roller.

3. In a coiler, a pair ofpinch rollers, means'for. driving the same, a swinging guide co-op e rz itir'ig. therewith for receiving material as delivered by being ,adapted to swing outwardly as the diameter of the coil increases,-

said rollers, saidg'uide a bending roller carried by said guide, means also carried by said guide for driving said bending roller, and coiling means co-operating with said bending roller.

4. In a coiler;a pair of pinch rollers, means for driving the same, a swinging guide co-operating therewith for receiving material as delivered by said rollers, said guide being adapted to swing outwardly as the diameter of the coil increases, a bending roller carried by saidguide, means also carried by said guide for driving said bending roller, and coiling means co-operating with said bending roller, said coiling meansv comprising a mandrel and a series of coiling rollers circumferentially disposed around the same.

5. In a coiler, a mandrel carrying a driven bending roller, a swinging guide carrying a driven bending roller, said guide being adapted to swing 6. In a coiler a mandrel carrying a driven bend ng roller, a movable guidecarrying a driven bending roller, and coiling means co-operating outwardly as the diameter of the coil increases 1 and coiling means co-operating therewith.

therewith, said ,coiling means comprising a series I of coiling rollers circumferentially disposed relative to said mandrel.

7. In a.,coiler, a mandrel carrying a driven bending roller, a movable guide carrying a driven bending roller, and coiling means co-operating therewith, said coiling means comprising a series of coiling rollers circumferentially disposed relative to said mandrel, one of said coiling rollers co-operating with the mandrel roller and the guide roller to form a set of bending rollers efiecv of said coiling rollers a roller carried thereby, driving means for said roller, and a plurality of coiling rollers disposed circumferentially'of said mandrel.

10. In a coiler, a stationary mandrel, a guide to convey material to be coiled, a set of driven coiling rollers arranged circumferentially around said mandrel, one of said coiling rollers being mounted in said guide andefiective for engaging guiding the material to be coiled, and a set of driven coiling rollers arranged circumferentially around said mandrel, one of said coiling rollers being mounted in said guide and efiective for engaging the material passing to the coiler and all being movable away from said mandrel to make room for a coil as it is formed.

12. In a coiler, a central mandrel,-a guide for guiding the material'to be coiled, and a set of driven coiling rollers arranged circumferentially around said mand'. 21, 'one of said coiling rollers being mounted in said guide and eilective for engaging the material passing to the cofler and all of said coiling rollers being movable away from saidmandrel to make room for a coil as it is formed, there being means for effecting said last-mentioned movementoi the ceiling rollers at a. decreasing rate of speed corresponding ap-- proximately to the decreasing rate at which the coil diameter increases.

13. In a coiler, a mandrel, a plurality of ceiling rollers co-operating with saidmandrel and divided into groups, a support for each group of coiling rollers, and driving meam carried by each support for the rollers 0! one group.

14. In a coiler, a mandrel carrying a driven bending roller, a movable guide carrying a driven bending roller, coiling means cooperating therewith, said coiling means comprising a series- 01' pairs of coiling rollers circumierentially disposed relative to said mandrel, andseparate driving means for each pair of coiling rollers.

15. In a coiler, a mandrel carrying a driven bending roller, a movable guide carrying a driven bending roller, coiling means cooperating therewith," said coiling means comprising a series of pairs of coilingmollers circumferentially disposed relative to said mandrel, and separ'a driving means for each pair of coiling roll said pairs or coiling rollers andthe driving therefor being mounted Ior movement toward. andaway from said mandrel.

16.'In a coiler, .a mandrel, a roller carried thereby, driving means for said roller, a movable- ,grows, means for feeding material to guide, a roller carried thereby, driving means for c I said roller, a plurality ofcoiling rollers disposed circumferentially of said mandrel, said coiling rollers being arranged in pairs, and driving means for each pair of coiling rollers.

17. In a coiler, a mandrel, a roller carried thereby, driving means for said roller, a movable guide, a roller carried thereby, driving means for said roller, a plurality of coiling rollers disposed and the first mentioned rollers and cooperating with. the first-mentioned rollers for bending the material to be cofled, means for rotating the coiling rollers and separate means for rotating the bending roller. 1

19. In a coiler, a mandrel, a plurality of coiling rollers circu'mterentially disposed around the mandrel, the rollers being arranged for movement outwardly from the mandrel the coil e coiler, and a movable guide extending from the. feed means and arranged to supply the material to the coiler, the guide carrying a roller so disposed as to engage the material passing to the coiler. 20. In a coiler, a mandrel, a set of coiling rollers arranged circumferentially around the mandrel, the coiling rollers being movable away coiling rollers toward the mandrel, means for.

moving the rollers outwardly in opposition tothe .biasing, means, and a lost motion connection in the roller moving means whereby the rollers may be moved outwardly by the growing coil if the roller moving means does not move'them outwardly with suil'icient rapidity.

21. In a coiler, a mandrel, an inside bending roller carried by the mandrel, outer coiling rollers cooperating with the inside bending roller to bend strip material supplied to the coiler, and

additional outer coiling rollers arranged around the mandrel for guiding and confining to coil form the bent material supplied'irom the firstmentioned rollers.

. LORENZ IVER-SEN.

ROBERT E. NOBLE. GUSTAF L. msx,

they "are moved during such means for biasing the 

